Dalsa PIRANHA CL-P1, Руководство пользователя

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«CamName» User’s Manual
20
DALSA Corp. 03-32-00253-13
Figure 7. Primary Points in a Lens System
Magnification and Resolution
The magnification of a lens is the ratio of the image size to the object size:
m
h
h
=
′
where m is the magnification, h’ is the image height (pixel size) and h is the object height
(desired object resolution size).
By similar triangles, the magnification is alternatively given by:
m
f
OD
=
′
These equations can be combined to give their most useful form:
′
=
′
h
h
f
OD
This is the governing equation for many object and image plane parameters.
Example : An acquisition system has a 512 element, 10µm pixel pitch line scan camera, a
lens with an effective focal length of 45mm, and requires that 100µm in the object space
correspond to each pixel in the image sensor. Using the preceding equation, the object
distance must be 450mm (0.450 m).
10
100
45
450 0 450
µ
µ
m
m
mm
OD
OD mm m
= =
( . )
3.6 EMC Operation
The Piranha has been designed for EMC compliance (see Appendix B for standards).
With the typical system as base, follow these specific guidelines to ensure best
performance:
•
Keep control and data cables as short as possible.
•
Ensure that all cable shields have 360
°
electrical connection to the connector.
•
Fasten and secure all DB25 connectors with screws.